1. Field of the Invention
The present invention relates to a removable fluid exchange system, connectable to an immovable device for the percutaneous passage of fluids and atraumatic access to a fluid circuit, such for example as a blood or lymphatic circuit in a living organism.
The invention concerns more particularly the head for connection to the atraumatic access device, implanted in the living organism, and its fluid supply device.
The fluids which may be exchanged with a living organ are blood but also pharmaceutical products such as insulin, antibiotics, vasodilators. Hemodialysis is an important case of blood exchange concerned by the system of the invention.
All these fluids are extracted from or injected into the living organism by means of a removable atraumatic access device, which is formed by a valve system establishing at will communication between the inside and the outside of the living organism. The implantation of such an atraumatic access device is justified by the traumatism and sclerosis of the living tissues created by repeated injection using hypodermic needles when repeated treatment is necessary.
2. Description of the Prior Art
Devices for atraumatic access to an internal circuit of the organism are known. Most of them have in common the fact of comprising a body, a part of which is in direct connection with the fluid circuit of the organism and another part of which, isolated from the preceding one by a valve, is in relation with the external environment of the organism. This second part forms a well giving access to the fluid network of the organism, such as the blood, although this example does not form a limit to the application of the invention; it passes through the derm or true skin, emerges at the level of the epiderm and, outside the periods during which fluid exchanges are practiced, is closed by any liquid and bacteria tight means. In this access well is disposed a valve, formed either by an extensible membrane, or by a membrane which can be pierced by a needle, or by a ball or by any mechanical valve, or by a rotary drum or else by the truncated cone shaped body of a plug cock. Some of these access systems to the blood network will be discussed further on.
Whatever the type of valve, there still remains a cavity formed by the access well, when the plug of the atraumatic device is removed.
It is known that the connection of tubes, in which fluids flow, to an immovable atraumatic access device leads to difficulties of poor disinfection, poor rinsing, poor air draining because the open ends of the tubes themselves are handled in the open air before the operation, and because of the presence of a well giving access to the air.
Up to now, the operation for making the ends of the tubes and of the access well aseptic has been carried out manually using an antiseptic product but, since it is carried out in the air, it is partially inefficient.
Furthermore, the antiseptic products used in manual asepsy are poorly rinsed by the rinsing products, for example inside the ends of the tubes, or in certain concave parts of the access well.
The problem of blood coagulation when it is a question of exchanges with the blood network through the tubes is partially solved, in the prior art, by heparine injections as required. Bubble removal is provided, in some systems, by at least one bubble remover integrated in the treatment apparatus, a dialyzer for example. But these solutions are only suitable for the part of the system through which blood is removed from the organism. In so far as the part is concerned through which a liquid, blood or a medicament, is reinjected into the blood vessel, there is always the risk of having a little air remaining in the tubes or in the access well, before the tubes are connected to the atraumatic access device and before the valve is opened. There is always then the risk of injecting a little air into the blood circuit, which is very dangerous to the organism.
The injection, or exchange of fluids with a living organism is therefore a delicate operation, presenting risks and expensive because it is carried out by a highly qualified staff.
One object then of the present invention is to simplify and make reliable the operations for connecting an immovable percutaneous passage device to a connection head, connected by at least two tubes to its fluid supply device, itself connected to a treatment apparatus such as a hemodialyzer or an insulin injector for example.
Another object of the invention is to ensure the aseptisization, rinsing and bubble removal of the whole part of a system included between the valve of the atraumatic access device and the treatment apparatus, the valve being closed before the beginning of the treatment.
A further object of the invention is to allow the connection of the connection head to the atraumatic access device in non aseptic conditions, then in practicing asepsis, rinsing and bubble removal, without breaking the asepsis in the aseptisized zone, using controls external to this aseptisized zone, which controls may be manual but are preferably automated.